TY - GEN
T1 - Hybrid single/multi-user MIMO transmission based on implicit channel feedback
AU - Kusume, Katsutoshi
AU - Khashaba, Karim
AU - Dietl, Guido
AU - Utschick, Wolfgang
PY - 2011
Y1 - 2011
N2 - This paper investigates multiple input multiple output (MIMO) transmission techniques based on realistic assumptions on feedback of channel state information. We consider three conventional techniques as the baseline: 3GPP long-term evolution (LTE) single user MIMO (SU-MIMO) based on implicit channel feedback, zero-forcing multiuser MIMO (ZF MU-MIMO) based on explicit channel feedback, and ZF MU-MIMO based on implicit channel feedback. SU-MIMO may not be able to exploit the full spatial dimension of the downlink MIMO channel. ZF MU-MIMO has the potential to improve the spectral efficiency, but the explicit channel feedback is not compatible with implicit feedback whereas implicit based ZF MU-MIMO is limited by performance and also the commonly assumed rank restriction makes it impossible to perform dynamic switching of SU/MU MIMO transmission. We propose a new hybrid scheme which enables such dynamic switching of SU/MU MIMO transmission by allowing UE to feed back the implicit channel information without any rank restriction. Computer simulation results show the benefits of the new hybrid scheme, which can properly switch to the better transmission mode in various correlation scenarios.
AB - This paper investigates multiple input multiple output (MIMO) transmission techniques based on realistic assumptions on feedback of channel state information. We consider three conventional techniques as the baseline: 3GPP long-term evolution (LTE) single user MIMO (SU-MIMO) based on implicit channel feedback, zero-forcing multiuser MIMO (ZF MU-MIMO) based on explicit channel feedback, and ZF MU-MIMO based on implicit channel feedback. SU-MIMO may not be able to exploit the full spatial dimension of the downlink MIMO channel. ZF MU-MIMO has the potential to improve the spectral efficiency, but the explicit channel feedback is not compatible with implicit feedback whereas implicit based ZF MU-MIMO is limited by performance and also the commonly assumed rank restriction makes it impossible to perform dynamic switching of SU/MU MIMO transmission. We propose a new hybrid scheme which enables such dynamic switching of SU/MU MIMO transmission by allowing UE to feed back the implicit channel information without any rank restriction. Computer simulation results show the benefits of the new hybrid scheme, which can properly switch to the better transmission mode in various correlation scenarios.
UR - http://www.scopus.com/inward/record.url?scp=80052152645&partnerID=8YFLogxK
U2 - 10.1109/icc.2011.5963117
DO - 10.1109/icc.2011.5963117
M3 - Conference contribution
AN - SCOPUS:80052152645
SN - 9781612842332
T3 - IEEE International Conference on Communications
BT - 2011 IEEE International Conference on Communications, ICC 2011
T2 - 2011 IEEE International Conference on Communications, ICC 2011
Y2 - 5 June 2011 through 9 June 2011
ER -